Fringe trimming method



1969 N. E. ELSAS ETAL 3,460,212

FRINGE TRIMMING METHOD Filed May 25. 1967 'INVENTOR) MAW/xv L. 254577/04/45 M flWl/MI United States Patent 3,460,212 FRINGE TRIMMENG METHODNorman E. Elsas, Atlanta, and Thomas M. Bryan 1!, Jefferson, 6a.,assignors of fifty percent each to Nemo Industries, Inc, Atlanta, Ga,and The Jefferson Mills, Incorporated, Jefierson, Ga., both corporationsof Georgia Filed May 25, 1%7, Ser. No. 641,352 Int. Cl. 1306c 13/00 US.Cl. 26-18%! 4 Claims ABSTRACT OF THE DISCLOSURE Fringe trimming methodfor trimming the loose threads from the edge of fabric, wherein thefabric is moved along a predetermined path, the loose threads of thefringe are urged away from the fabric in a plane parallel to the fabricso as to unsnarl the individual threads from one another, the loosethreads are urged in a direction normal to the plane of the fabric, theedge of the fabric determined, and the threads are urged away from andparallel to the surface of the fabric, whereupon cutting means sever thefringe from the fabric.

Background of the invention When weaving fabrics, some fabrics are wovenwith a fringe of loose threads along one edge thereof. This fringe isinherently uneven because of the weaving process, and it is desirablethat the fringe be trimmed from the fabric before the fabric isprocessed through finishing operations since the fringe can interferewith the guiding and holding of the fabric during the finishingoperations.

Usually the edge of the woven fabric in which fringes of loose threadsare present curves so that the edge of the fabric is not perfectlystraight. When the fringe is being cut from the fabric the cuttingdevice should be constantly repositioned with respect to the fabric toproperly trim the fringe threads away from the fabric. When trimming thefringe of the fabric by mechanical means as the fabric is processedthrough the various other finishing steps, it is difiicult to ascertainthe exact edge of the fabric through the mass of loose threads presentin the fringe since these threads tend to tangle among themselves toform lumps which might be mistaken by mechanical sensing means as theedge of the fabric.

Summary of the invention This invention comprises a fabric fringetrimming method and apparatus including the steps of urging the fringethreads away from the fabric in substantially the same plane occupied bythe fabric so as to untangle and straighten the fringe threads, urgingthe threads in a plane normal to the plane occupied by the fabric toexpose the edge of the fabric at the base of the fringe threads, sensingthe edge of the fabric at the base of the fringe threads while thefringe threads extend in a plane normal to the plane occupied by thefabric, urging the fringe threads away from the fabric in the directiongenerally coextensive with the plane occupied by the fabric, andtrimming or cutting the fringe threads away from the fabric. Streams ofair are directed toward the fringe threads to orient the threads asdesired, and photoelectric sensing elements or feeling members areutilized to determine the edge of the fabric at the base of the fringethreads.

Accordingly, it is an object of this invention to provide a method oftrimming a fringe of loose threads from an edge of woven fabric, whereinthe edge is accurately trimmed in spite of the unevenness of the edge ofthe fabric.

"ice

Another object of this invention is to provide a method of economicallytrimming a fringe of loose threads from an edge of fabric atsubstantially any distance desired from the edge of the fabric.

Another object of this invention is to provide apparatus foreconomically and expediently trimming the loose fringe threads from awoven fabric, which is adapted to be combined with apparatus formanufacturing or otherwise processing the fabric.

Another object of this invention is to provide apparatus for trimmingthe loose fringe threads from fabric which functions to cut the threadsat a predetermined distance from the edge of the fabric in spite of thecrookedness of the edge.

Another object of this invention is to provide apparatus for trimmingthe loose fringe threads from a woven fabric, which accuratelydetermines the edge of the fabric adja cent the fringe, cuts the fringethreads at a predetermined distance from the edge of the fabric, andcompensates for any curves or crookedness in the edge of the fabric.

Other objects, features and advantages of the present invention willbecome apparent upon reading the following specification when taken inconjunction with the accompanying drawing.

Brief description of the drawing FIG. 1 is a schematic perspective viewof the fringe trimming apparatus.

FIG. 2 is a partial perspective view of the fringe trimming apparatus.

FIG. 3 is a schematic view of the control mechanism utilized to move themovable frame of the fringe trimming apparatus.

FIG. 4 is a bottom perspective view of the fabric as it passes beneaththe photoelectric cell.

FIG. 5 is a bottom perspective view, similar to FIG. 4, but showing anedge feeler.

FIG. 6 is a side elevational view of the contact roll utilized to drivethe anvil of the cutting mechanism.

Description of the embodiments Referring now more particularly to thedrawing, in which like numerals indicate like parts throughout theseveral views, FIG. 1 shows, schematically, the fabric as it isprocessed through fringe trimmer 9. The fabric 10 is moved in thedirection indicated by arrow 11 over rollers 12 and 13 which are part ofthe fabric manufacturing or processing apparatus. A plurality of airducts are placed at spaced intervals along the path of fabric 19 as itpasses from roller 12 to roller 13. Air ducts 15 and 16 are positionedabove and below the fabric 10, respectively, and the exhaust ends 17 and18 of air ducts 15 and 16 are oriented toward the edge 19 of the fabric10 which carries fringe 20 so that the air flowing through these ductsand out of the exhaust ends 17 and 18 functions to blow the fringethreads 20 away from fabric 10, so that the fringe threads standlaterally away from the fabric.

Air duct 21 is positioned above the path of travel of fabric 10 and itslower exhaust end 22 is positioned above the fringe 20 of the fabric.Air duct 21 and its exhaust end 22 function to duct air in a downwarddirection, generally perpendicular to the plane of the fabric 10, so asto urge the fringe threads 20 in a downward direction. A light source 23is positioned below the plane of the fabric 18, below edge 19, and apair of photoelectric cells 24 are positioned above the plane of fabric10, above light source 23. Light source 23 and photoelectric cells 24are positioned closely adjacent air duct 21, where the fringe threads offabric 10 extend in a downward direction from the influence of the airpassing through air duct 21.

Air ducts 25 and 26 extend toward fabric 10, from above and below theplane of the fabric, respectively, and their exhaust ends 27 and 28 areconstructed in a manner similar to the exhaust ends 17 and 18 of airducts and 16, so that the air passing through ducts and 26 urges thefringe threads to extend laterally from fabric 10, in the same planeoccupied by the fabric 10. An anvil 29 is positioned below fabric 10,and constructed to rotate in the direction as indicated by arrow 30. Thesurface of anvil 29 is in tangential contact with the lower surface offabric 10 and moved at a speed slightly faster than the fabric 10. Acutting disc 31 is positioned above fabric 10 and biased toward anvil29. Cutting disc 31 and anvil 29 are adjustable so that cutting disc 31is automatically positioned at the edge 19 of fabric 10 and the fringethreads 20 will be cut or crushed from the edge of the fabric. Vacuumconduit 32 is positioned below the plane of fabric 10, adjacent anvil29. Vacuum conduit 32 is connected to a source of vacuum (not shown) andany fringe threads removed by cutting disc 31 will be removed from thevicinity of fringe trimmer 9" by vacuum conduit 32.

As is best shown in FIG. 2, fringe trimming apparatus 9 is mounted on astationary base or platform 34 which can be connected to othercomponents of the assembly line or supported from the surface of thefloor. A pair of slot-ted support members 35 and 36 are rigidlyconnected to the upper surface of platform 34, in inward facingrelationship, and movable platform 38 is slidably received therein.Rotatable anvil 2.9 is supported on movable platform 38 by hearingblocks 39 and 40. L-shaped support frame 41 is supported by, and movablewith, movable platform 38 by means of stanchion 42. Support frame 41includes a base member 44 extending parallel to the axis of rotation ofanvil 29, over the plane of fabric 10, and leg 45 which extends parallelto the direction of the path of travel of the fabric 10. A pair ofstationary tensioning bars 46 and 47 are supported in a horizontal planeby leg 45 at its end remote from base member 44. Tensioning bars 46 and47 extend perpendicular to the path of travel of fabric 10, and thefabric is arranged to pass beneath tensioning bar 46 and over tensioningbar 47.

Driving mechanism 49 is supported by leg 45 of support frame 41. Drivingmechanism 49 includes a shaft 50 rotatably mounted in bearing block 51which is connected to leg 45. Contact roll 52 is rigidly connected toshaft 50 by discs 54 and 55. Contact roll 52 is elastic and positionedabove tensioning bar 47 and engages fabric 10 as it passes overtensioning bar 47. The diameter of contact roll 52 can be varied byadjustinng disc 55 closer to or further away from disc 54 by means ofnuts :6. Flexible drive shaft 58 is connected at one of its ends torotatable drive shaft 50, and at the other of its ends to anvil 29.Thus, rotation of contact roll 52 in the direction as indicated by arrow59 by frictional engagement with the moving fabric 10 causes anvil 29 torotate in the direction as indicated by arrow 30.

Manifold 60 is mounted on leg 45 of support frame 41, and a source ofcompressed air (not shown) communicates with inlet duct 61. Air ducts15, 16, 21, 25 and 25 communicate with manifold 60 and duct air towardfringe 20 of fabric 10, as previously explained. Air duct 62communicates at one of its ends with manifold 60, and at the other ofits ends with pressure control valve 64. Pressure control valve 64 is ofconventional design and includes gauge 65 and control knob 66. Air duct68 communicates at one of its ends with the outlet 69 of control valve64, and at the other of its ends with fluid cylinder 70. Cutter dischousing 71 is supported by base member 44 of support frame 41, and fluidcylinder is mounted above housing 71. Fluid cylinder 70 includes apiston (not shown) which is urged in a downward direction by the airpressure admitted to fluid cylinder 70 through air duct 63, and thepiston is connected to the axle (not shown) of cutter disc 31. Thus, theair pressure communicating with fluid cylinder 70 urges cutter disc 31toward anvil 29. Control valve 64 controls the pressure of air admittedto fluid cylinder 70, and thus the force with which cutter disc 31 isurged toward anvil 29.

Light source 23 is mounted on movable platform 38, and the pair ofphotoelectric cells 24 is suspended above light source 23 by means ofsupport bracket 72. Support bracket 72 is adjustable and comprisessupport arm 74 rigidly attached to leg 45 of support frame 41, andadjustable arm 75. Adjustable arm 75 can be moved toward or away fromleg 45 by means of slots 76 sliding over bolts 78. Also, the pair ofphotoelectric cells 24 is rotatably mounted in adjustable arm 75, sothat the effective distance between the pair of photoelectric cells withrespect to the edge 19 of fabric 10 can be varied.

The pair of photoelectric cells 24 is electrically connected to junctionbox 79 by means of electric conductors 80. Junction box 79 is connectedby electrical conductors 81 and 82 from opposite ones of the pair ofphotoelectric cells 24 to solenoid control valves 83 and 84. Air duct 85is connected at one of its ends to manifold 60, and at the other of itsends to solenoid control valve 83, while air duct 86 is connected at oneof its ends to manifold 60 and at the other of its ends to solenoidcontrol valve 34. Fluid cylinder 88 is rigidly connected to stationaryplatform 34 by means of brackets 89. A piston 90 (FIG. 3) is slidablyreceived in cylinder 88 and includes shafts 91 and 92 extending throughopposite ends of cylinder 88. Shaft 91 is connected at its outer end tolinkage 94. Linkage 94 includes pivotal link 95 connected to shaft 91 atone of its ends and pivotally connected to station ary platform 34 atthe other of its ends by means of pivot pin 96. Connecting link 98 isconnected at one of its ends to pivotal link 95 at a point intermediatethe ends of pivotal link 95, and at its other end to movable platform38, by means of pivot pins 99 and 100.

Fluid cylinder 88 communicates at each of its ends by means of air ducts101 and 102 with solenoid control valves 83 and 84. Solenoid controlvalves 83 and 84 each include control spool 104 with valve spools 105and 106 maintained in spaced relationship by connector 107. Bleedervalves 109 are connected to solenoid control valves 83 and 84. Controlspools 104 are normally maintained in their down position, as shown inFIG. 3, so that air ducts S5 and 86 normally communicate with air ducts101 and 102. When the coil of the solenoid is energized control spools104 will be moved against the bias of their springs 110 to an upwardposition where air ducts 85 and 86 will be blocked by valve spools 105and air ducts 101 and 102 will be in communication with bleeder valves109.

As is best shown in FIG. 4, light source 23 is positioned below theplane of fabric 10, at the edge 19 of the fabric and the pair ofphotoelectric cells 24 is positioned above the plane of the fabric 10,directly above the light source 23. With this arrangement, the pair ofphotoelectric cells will sense when the edge 19 of the fabric 10 ispositioned between photoelectric cells 24a and 2412 since cell 24a willhave the light beam from light source 23 blocked by the fabric 10 andcell 24]) will be exposed to the light beam. If the edge 19 is notdisposed between cells 24a and 24b, either both cells will be exposed tothe light source 23 or the light beam from light source 23 will beblocked from both cells.

If desired, the photoelectric sensing apparatus can be replaced by amechanical feeler as shown in FIG. 5. Feel-er 112 is suspended frombalancing arm 114 in a position where it engages the edge 19 of fabric10. A wand 115 is rigidly connected to feeler 112 and extends in anupward direction from balancing arm 114. A pair of microswitches 116 and117 is positioned on each side of wand 115, and the switches areelectrically connected to solenoid control valves 83 and 84. With thisarrangement, feeler 112 is firmly urged toward the edge 19 of fabric 10,and any irregularity in the edge of the fabric will cause feeler 112 topivot about balancing arm 114. Pivoting of feeler 112 in this mannercauses its wand 115 to close either microswitch 116 or 117, dependingupon the direction of movement of feeler 112. Thus, the position of edge19 of the fabric is determined by the mechanical feeler.

Operation In operation, the fringe cutting apparatus 9 is positionedwith other material processing equipment in the path of travel of thefabric, either by mounting the apparatus directly onto the associatedequipment or by supporting the stationary platform 34 from the fioorsurface. The fabric is fed between tensioning bars 46 and 47, belowtensioning bar 46 and over tensioning bar 47, and movable platform 38 isadjusted in its support members 35 and 36 so that cutting disc 31 is inthe vicinity of the fringe 20 of the fabric 10. The contact roll 52 ofdriving mechanism 49 engages the upper surface of the fabric as ittravels over tensioning bar 47, and the movement of the fabric causescontact roll 52 to rotate, which rotates flexible shaft 58 and causesanvil 29 to rotate. Contact roll 52 rotates in the direction asindicated by arrow 59 while anvil 29 rotates in the direction asindicated by arrow 30. It is desirable to rotate anvil 29 so that itssurface contacting the bottom surface of fabric 10 moves at a linearvelocity slightly faster than the linear velocity of fabric 10 to keepthe fabric in tension. Thus, contact roll 52 is of slightly smalldiameter than that of anvil 29. If it is desired to rotate anvil 29 at ahigher or lower speed, contact roll 52 may be made smaller or larger byadjusting the distance between discs 54 and 55, thereby changing thediameter of the elastic contact roll 52.

Air is ducted to manifold 60 from a compressor (not shown), and the airpassing through manifold 60 is ducted to the various air ducts of theapparatus. The air passing through ducts and 16 impinges upon the fringethreads of the fabric in a direction to urge the fringe threads to standlaterally away from the fabric, generally in the same plane as the planeof the fabric. This tends to comb or straighten the fringe threads andto remove any tangles in these threads. As the fabric 10 continues tomove in the direction as indicated by arrow 11, the air passing throughduct 21 impinges upon the fringe threads in a direction generally normalto the plane of fabric 10, from above the fabric, so that the fringethreads tend to stand in a downward direction from the plane of thefabric. Light source 23 and the pair of photoelectric cells 24 arepositioned closely adjacent to air duct 21 so that the light emanatingfrom light source 23 will not be blocked by the fringe threads. Thus,photoelectric cells 24 determine the edge of the fabric withoutinterference from the fringe threads.

As the fabric 10 continues to move in the direction indicated by arrow11, air ducts 25 and 26 again urge the fringe threads to stand laterallyaway from fabric 10. Anvil 29 and cutting disc 31 are positioned closeto air ducts 25 and 26 so that the fringe threads are received on anvil29 as they extend laterally from fabric 10. As the fringe threads moveover anvil 29, cutting disc 31 severs the fringe threads from fabric 10.The threads severed from the edge of the fabric are received in vacuumconduit 32 and removed from the area of anvil 29.

such that a minimum of drag or friction is encountered by the edge 19 ofthe fabric as the fringe threads are removed from the fabric.

As is shown in FIG. 4, photoelectric cells 24a and 24b are positionedabove the edge 19 of fabric 10 while light source 23 is positioned belowthe fabric. If movable platform 38 is properly positioned so thatcutting disc 31 functions to sever the fringe threads from the fabric ata proper distance from the edge 19 of the fabric, photoelectric cell 24awill be blocked from light source 23 by fabric 10 while photoelectriccell 24b will be exposed to the light. With any irregularity in the edge19 of the fabric, such as a curve in the edge of the fabric, eitherphotoelectric cell 24a will be exposed to light source 23, orphotoelectric cell 2412 will be blocked from light source 23. Whenphotoelectric cell 24b is blocked from light source 23, solenoid controlvalve 84 is energized and its control spool 104 is moved (FIG. 3) toblock air duct 86 and allow air duct 102 to communicate with bleedervalve 109. This causes piston 90 to move in cylinder 88 away from theedge 19 of the fabric 10 to move movable platform 38 away from the edgeof the fabric. Movement of platform 38 in this manner carries supportframe 41 and its related components, including anvil 29, cutting disc.31, light source 23, photoelectric cells 24, and the air ducts awayfrom the edge 19 of the fabric. Thus, cutting disc 31 is repositioned sothat it cuts the fringe threads at the proper distance from the edge 19of the fabric. As the movable platform 38 is repositioned, photoelectriccell 24b will again be exposed to light source 23, whereupon solenoidcontrol valve 84 will be deactuated, its spring 110 moving its controlspool 104 to the position as shown in FIG. 3, where air duct 86 againcommunicates with air duct 102. This tends to equalize the pressure onboth sides of piston 90, thereby stabilizing linkage 94.

When the edge 19 of the fabric 10 is irregular and exposes photoelectriccell 24a to light source 23, solenoid control valve '83 will beenergized to block duct and allow duct 101 to communicate with bleedervalve 109 of valve 83. Thus, the pressure from cylinder 88 will be bledthrough duct 101 and the pressure of the air present on the other sideof piston 90 will move piston 90, linkage 94 and movable platform 38toward the edge 19 of the fabric 10, thus repositioning cutting disc 31,anvil 29, and their related components. When photoelectric cell 2411 isagain blocked from the light, light from light source 23, solenoidcontrol valve 83 will again be deactuated, whereupon the system is againstabilized.

It should be noted that shafts 91 and 92 extend from both sides ofpiston 90, through the end walls of cylinder 88 so that equal areas arepresented on each side of piston 90 for the air pressure within cylinder88. Thus, equal air pressure present on both sides of piston 90 willexert equal forces on piston 90. Accordingly, when both solenoid controlvalves 83 and 84 are deactuated and in their open position so that thesource of air pressure communicates with cylinder 88 on both sides ofpiston 90, the system will be stabilized and there will be no movementof movable platform 38. When one of the solenoid control valves 83 or 84is actuated to block the source of air pressure to one side of piston90, the rate at which the air from cylinder 88 escapes through itssolenoid control valve will be determined by the adjustment of thebleeder valve 109 of the solenoid control valve. Thus, if the fabric 10is moved at a high rate of speed and there is a short distance betweenphotoelectric cells 24 and cutting disc 31, bleeder valves 109 should beadjusted so that the air can be bled from cylinder 88 at a rapid rate sothat there will be little delay in repositioning cutting disc 31 when anirregularity is determined by photoelectric cells 24. Of course, iffabric 10 is processed at a slower rate, bleeder valves 109 can beadjusted to restrict the flow of air therethrough so that the air isbled more slowly from cylinder 88, thus providing a longer delay time inrepositioning cutting disc 31.

Linkage 94 between cylinder 88 and movable platform 38 is such that alarge movement of piston 90 is required to move platform 38. Pivot pin99 can be positioned in any of the apertures present in pivot link 95 tovary the amount of movement necessary of piston 90 to move platform 38 agiven distance. Under normal circumstances, it is anticipated that athree to one or four to one linkage will be utilized, thus requiringfour inches of movement of piston 90 to achieve one inch movement ofmovable platform 38. With this arrangement, fine control is maintainedover the movement of cutting disc 31.

Photoelectric cells 24a and 24b are spaced apart a distance calculatedto prevent searching or hunting of the system; that is, to keep thefringe cutting apparatus from oscillating back and forth during itscutting function due to over-compensation of the automatic controls ofthe system. Photoelectric cells 24a and 24b are mounted in a disc whichis supported by support bracket 72 so that the disc can be rotated tochange the position of photoelectric cells 24a and 24b. While thephotoelectric cells are shown in FIG. 4 as being disposed with respectto each other along a line extending transversely with respect to theedge 19 of fabric 10, the disc can be rotated to effectively bring thecells closer to the edge 19 of the fabric, thus effectively reducing thedistance between the cells. When the cells are oriented in this manner,a smaller variation in the smoothness of the edge 19 of the fabric willcause a repositioning of the fabric cutting apparatus. As applied to themechanical feeler of FIG. 5, a similar function can be achieved bymoving microswitches 116 and 117 closer to or further away from eachother.

At this point, it should be apparent that the manner in which the air isblown over the edge of the fabric is effective to first comb orstraighten the fringe threads, secondly to blow the fringe threads in adirection normal to the plane of the fabric so as to expose the trueedge of the fabric, and thirdly to re-orient the fringe threads so thatthey extend laterally from the fabric and are easily cut by cutting disc31. The use of photoelectric cells 24 is such that the true edge of thefabric can be determined without making physical contact with the edgeof the fabric. If it is desired to cut the fringe threads closer to orfurther away from the edge of the fabric, all that is necessary inmaking this adjustment is to extend adjustable arm 75 of support bracket74 further away from or closer to leg 45 of support frame 41, whichrepositions photoelectric cells 24. This causes the anvil 29 to shiftthe edge of the fabric with respect to the cutting disk 31 since thecutting disk 31 does not move rapidly with respect to the fabric. Thus,cutting disc 31 will be efiective to leave a longer or shorter fringe atthe edge of the material.

While air ducts '15 and 16, and 25 and 26 have been shown as blowing airfrom above and below the fabric, the use of only a single duct or 16, or25 or 26 is suflicient in most instances to achieve substantially thesame function since the air flow over only one surface of the fabric issufficient to induce the fringe threads to stand outwardly from thefabric 10. Also, while air ducts, 15, 16, 21, 25 and 26 have beendisclosed as blowing air over the surface of the fringe, it should beunderstood that any one or all of these ducts oriented can be replacedwith vacuum ducts to induce an air flow in a similar manner. The use ofvacuum ducts with some types of materials has the advantage of removinglint and loose threads from the vicinity of the fringe cuttingapparatus. Also, while ducts 15, 16, 21, 25 and 26 have been disclosedas air ducts, it should be understood that other fluids may be utilizedin these ducts to perform substantially the same function.

While anvil 29 has been illustrated as being driven by driving mechanism49, it should be understood that in some installations it may bedesirable to drive anvil 29 by direct linkage to the drive system of theassociated equipment. A linkage of this type can be utilized withoutdetrimental effect on the remaining components of the system.

It will be obvious to those skilled in the art that many variations maybe made in the embodiments chosen for the purpose of illustrating thepresent invention.

We claim:

1. A method of cutting loose threads along the edge of a moving fabriccomprising:

(a) extending the loose threads in a direction generally normal to theplane of the fabric;

(b) sensing the true edge of the fabric at the base of the loosenormally extending threads to properly determine the cutting position;

(c) urging the loose threads away from the fabric in a directiongenerally coextensive with the plane of the fabric to properly positionsuch threads for cutting; and,

((1) cutting at least a portion of the length of the loose threads fromthe fabric, the cutting position being modified in accordance with thesensing whereby the cutting of the threads is maintained at apredetermined distance from the true edge of the fabric.

2. The method of claim 1 wherein step (a) is performed by discharging astream of fluid against the loose threads in a direction generallynormal to the plane of the fabric.

3. The method of claim 1 further comprising the step of extending theloose threads away from the fabric in a direction co-extensive with theplane of the fabric prior to step (a) to unsnarl the loose threads.

4. The method of claim 1 wherein step (c) is performed by discharging afirst stream of fluid against the loose threads above the plane of thefabric in a direction generally parallel to the plane of the fabric andsimultaneously discharging a second stream of fluid against the loosethreads below the plane of the fabric and in a direction generallyparallel to the plane of the fabric.

References Cited UNITED STATES PATENTS 410,655 9/1889 Smith 26-1041,973,104 9/1934 Richardson 26-104 2,110,567 3/1938 Burr 2610.42,962,791 12/1960 Remington 2610.4 3,409,955 11/ 1968 Holm 26-104 ROBERTR. MACKEY, Primary Examiner US. Cl. X.R. 139-302

